The present disclosure relates to a U-bend pipe type heat exchanger, and, more particularly, to a U-bend pipe type heat exchanger which includes a heat exchanger main body having a plurality of U-bend pipes, each of which is configured by integrating heat exchange pipes and a U-shaped pipe, and performs heat exchange between a low-temperature water and a heat source.
A heat exchanger crosses a heating fluid and a heating target fluid differing in temperature from each other to allow heat delivery therebetween, and is used to heat a low-temperature water circulating in a boiler or a water heater to supply a hot water or a heating water.
In the heat exchanger, a plurality of heat exchange pipes installed in a main body of the heat exchanger is connected with one another at both sides of the main body, whereby a low-temperature water circulates in the main body in a zigzag direction. Such heat exchanger is classified into a U-shaped pipe type or a water jacket type depending on a type of connector.
As illustrated in FIG. 1, in a U-shaped pipe type heat exchanger which is disclosed in, for example, Korean Laid-open Patent Publication No. 10-2010-0032543, a plurality of heat exchange pipes 30 is installed in a heat exchange chamber 40 and U-shaped pipes installed at side surfaces of a main body of the heat exchange chamber 40 connect neighboring heat exchange pipes 30.
As illustrated in FIG. 2, in a water jacket type heat exchanger which is disclosed in, for example, Korean Laid-open Patent Publication No. 10-2010-0115601, a plurality of heat exchange pipes 10 interposed between a first fixing plate 21 and a second fixing plate 22 is connected with one another through a parallel fluid passage caps (water jackets) 31.
However, in the U-shaped pipe type heat exchanger, the heat exchanger increases in overall size thereof because the U-shaped pipes protrude outward from the main body. Further, thermal efficiency is lowered because heat dissipation in the U-shaped pipes exposed outside generates heat loss.
The aforementioned defects of the U-shaped pipe type heat exchanger can be compensated by means of the water jacket type heat exchanger. However, the water jacket type heat exchanger does not satisfy high-level pressure-resistance test criteria. That is to say, in the water jacket type heat exchanger, deformation by pressure or damage may occur due to expansion of side surfaces of the heat exchanger by pressure or insufficient uniformity in brazing during a manufacturing process.